5
3
MECHANICAL INSTALLATION
3.2.2
Velocity Limitations – Figs. 3.4 to 3.6
All insertion probe devices are susceptible to the vortex shedding effect which can cause severe vibration of the probe, resulting
in damage and/or measurement instability. Electromagnetic devices with no moving parts, such as AquaProbe, are less
susceptible to this effect than mechanical devices.
The graphs below show the maximum permissible velocities, depending the probe's location.
0
100
200
300
400
500
600
700
800
900
1000
0
1.0
2.0
3.0
4.0
5.0
6.0
Insertion Length in mm
Maximum V
elocity in m/s
0
3.0
7.0
10.0
13.0
17.0
Maximum V
elocity in ft/s
20.0
4
8
12
16
20
24
28
32
36
40
Insertion Length in inches
Fig. 3.6 Maximum Permissible Velocity for different Insertion Lengths
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0
1.0
2.0
3.0
4.0
5.0
6.0
Pipe Size in mm
Maximum V
elocity in m/s
Maximum V
elocity in ft/s
0
3.0
7.0
10.0
13.0
17.0
20.0
8
16
24
32
40
48
56
64
72
80
Pipe Size in inches
Fig. 3.4 Maximum Permissible Velocity for different Pipe Sizes
Fig. 3.5 Maximum Permissible Velocity for different Pipe Sizes
Traversing
Mean Axial Velocity Method
(
1
⁄
8
Diameter)
Centre Line Method
0
1000
2000
3000
4000
5000
6000
7000
8000
0
1.0
2.0
3.0
4.0
5.0
6.0
Pipe Size in mm
Maximum V
elocity in m/s
0
3.0
7.0
10.0
13.0
17.0
20.0
Maximum V
elocity in ft/s
40
80
120
160
200
240
280
320
Pipe Size in inches
Содержание Kent-Taylor AquaProbe
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